Hydrocache

From Cacheopedia

Hydrocache is distinct from an underwater cache.

Hydros do not need to be under water but merely are on water/require a vessel to reach.

An example of a hydrocache would be an ammo can concealed on a small island in the middle of a river or lake. A cache-hunter would merely use a kayak, canoe, or jet-ski (or other type of watercraft) to reach the cache.

As always, make sure the cache is sealed when you're through to avoid moisture from getting inside.

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